Piston ring



Patented Sept. 6, 1949 PISTON RING Harold P. lPhillips, Hastings, Mich., assignor to Hastings Manufacturing Company, Hastings,

Mich.

Application August 30, 1948, Serial No. 46,900 9 claims. (o1. sos-4s) This invention relates to improvements piston rings.

' The main objects of the invention are:

First, to provide a piston ring assemblywhich is highly eflicient from the standpoint of effective sealing and also from the standpoint of oil control.

Second, to provide a ring assembly in.which there is no gap opening thereby permitting effective sealing. and the prevention of blow-by.

Third, to provide a ring assembly which facilitates assembly of the parts in exact operative position and maintenance thereof in such position during operative use.

Fourth, to provide a piston ring assembly which provides improved tensioning of the ring segments against the cylinder wall.

Objects relating to details and economies of my invention will appear from the description to follow. The invention is pointed out and dened in the claims. Y

. A preferred embodiment of my invention is illustrated in the accompanying drawing. in which:

Fig. 1 is an enlarged fragmentary .view showing in section a cylinder, a piston, and a ring assembly assembled in the groove ofthe piston, the ring assembly being shown4 in section on the line l-..-I of Fig. 2. Y

Fig. 2 is an enlarged fragmentary edge-view of the piston ring assembly showing the relative position of the parts when viewing -oneof the side edges of the assembly.

Fig. 3 is an enlarged fragmentary edge View of the ring assembly showing the relative position of the parts when viewingthe assembly opposite from that shown in Fig. 2.

. Fig. 4 is a plan view of a cylinder wall engaging ring sidemember of the assembly.

. Fig. 5 is .a .perspective view ofthe-upper an lower cylinder wall engaging ,sidemembers of the assembly, said side members being integrally connected by an axially extending offset portion.

-The assembly herein disclosed isa modification of that disclosed in my copending application for piston rings, Serial Number 722,699, led January 17, 1947, now Patent No. 2,460,431.

In considering the accompanying drawing it should be borne in mind that no attempt has been made to show the` parts in their relative proportion andwhere associated with the piston to show the clearances and relative dimensions.

. In the embodiment of my invention illustrated I. designates the piston and 2 the .cylinder of an internal combustion engine.. The. piston ispro-` vided with a groove 3' and oil drainage passage lileading from the bottom of the groove through the .piston wall. Disposed in the groove 3 is the piston ring or piston ring assembly designated generally by the reference numeral 5. An expander spring 6 of sinuous form as is common' in the .art-engages the inner side of the ring assembly to for-ce the same into engagement with the cylinder Wall. f-

My improved ring assembly comprises a pair of spaced thin steel expansible upper and lower side members 1 and 8 integrally connected by the vaxially extending offset portion 9. In practice the side members 1 and 8 are formed of one continuous piece of fiat steel stock coiled edgewise. The upper side member 1 extends from the free end IU thereof to the lateral oset 9 and the opposite end portions 1| and 1H thereof overlap for approximately The side member 1 is provided with an axially Aextending offset portion Il and its free endV I0 terminates in slightly spaced relation from this offset portion to permit contraction and expansion of the side member when the assembly is placed in the ring groove. Similarly the side member 8 extends from its free end l2 to the lateral offset 9, and the opposite end -portions 8l Uand 3H thereof overlap for approximately 1809. rThe side memberv 8 is provided with an axially bent offset portion 13,and itsY free end I2 terminates in slightly spaced relation from this oiset portion to permit contraction and expansion of the side member when the assembly is placed in the ring groove. The side members 1 and .8 are so formed that when in position in the piston ring groove 3 they are under compression and urged yieldingly outwardly against the cylinder .walh 'l Y The axially bent or offset portion 'Il in the upper-side member 'lextends an axial distance approximatelyequal to the thickness of the stock of the side member. This permits the lower overlapping end portion 1H to-be beneath the generalplane of the side member and permits the upper surface 'of the side member to be all substantiallyina plane so as to engage the upper wall -of the ringgroove 3 throughout substantially the entire-circumference thereof, suchV engagement Abeing -permittedexcept for the relatively short-distance-betweenthe end l0 and-the offset or bent-portion Il, asshown in Fig, 3. Likewise, the bent-oroiiset portion 4I3 ofthe lower side member 8 extends an --axialdistance approximately equal-to the thickness of the stock of the side member and this permits the upper overlapping endportion-to be above the general plane 7' of the side member and permits the lower surface of the side member to be all substantially in a plane so as to engage the lower wall of the ring groove throughout substantially the entire circumference thereof, such engagement being permitted except for the relatively short distance between its free end I2 and the offset or bent portion I3 as shown in Fig. 3.

The side members 'I and 8 .are held spaced relation by the intermediate or spacer member I4. The combined thickness of the side members and spacer member is such as to fit the ring groot/,e 3 with the necessary clearance to permit expansive movement without binding. The spacer member I4 is formed of ductile metal foldedfupen itself into a plurality I or folds disposed in side by side relation, the upper ply I5 in each of the opposite halves I6 and I'I thereof being flat and the remain-ing 4lower plies being conformed to provide alternate spacer and drain reaches I8 and I9, respectively. The drain -reaches I9 provide passageways 2l! through the ring assembly `for passage of oil therethrough to the rear of the ring assembly and then .to the oil drain openings d through the piston wall.

The spacer member I4 has a split or joint 2l with the ends o n the `opposite sides of the joint spaced as shown in Fig, '2 to permit contraction and expansion of the spacer when placed in the ring groove. Located in this space between ,the

ends of the spacer is the bent or offset portion 9 connectinglthe lower endportion II I of the upper side member I-to the upper end portion BI I of the lower side member 8. Opposite' from its split or joint 2|, vthe spacer element is provided with a relatively short axially bent or oiset portion 22 v extending axially of the ring assemblyV to permit the diametrica-lly opposite side portions I5 and II on the opposite sides ofthe ogset portion 22 to lie in parallel axially spaced planes. When the Yspacer member I4 is in assembled relation with the side members I and 8 in the ring groove, the lower end portion "I II of the upper side member TI overlappingly engages the lower oiiset portion I'I of the spacer, and the upper end portion lI-I of vthe lower side member -8 overlappingly engages the upper oiset portion I6 of thespacer, as shown in Fig. 2. Also when the side members 1 and 8 and spacer I4 are in assembled relation inthe ring .groove their axially bent portions II, I3 and '22 are in substantially parallel superimposed relation, as shown in Fig. 3. The spacer member I4 :is under compression and is urgedyieldingly outwardly by its tension against the cylinder wall. Providing the connecting axially extending ofiset portion 9 between the upper'and lower side and disposing the same in the gap between the spaced ends of the spacer, oppoaxially bent offset portion A22 in the spacer, provides a very simple means llimiting 0r preventing circumferential shifting of the spacer element relative to side members 'I and 8 and consequent binding of the ring elements where the axially bent offset portion 22 is -formed in the spacer. The crossing over through the gap also facilitates installation, inasmuch as it gives a locating point of the one and one half wrapped side members relative to the offset spacer.Y

Also from the standpoint of improvement in performance the cross-over suits in the coils around thebistpn being multiplied from two one and one half turns acting of integrally connected plies separately to a total of three acting together. The fact must be kept in mind that all cylinders are tapered when hot and at normal running temperature, therefore, in new supposedly straight cylinders, a snubbing action is developed as the ring moves down the cylinder wall and a corresponding releasing action occurs as the ring moves .up .the cylinder wall. This snubbing and releasing action is further increased in worn cylinders which makes an increase in snubbing for worn cylinders desirable.

My improved composite piston ring or ring assembly is highly efficient from the standpoint of ,oil control, `sealing or blow-by prevention and ,generally improved performance. It is desirable for use in new engines and is especially desirable for use with old or worn cylinders and pistons. '-I-t may be very economically produced and readily assembled and when assembled the parts are securely retained against relative circumferential shifting without binding action in the ring groove.

I have described and illustrated and .embodiment or adaptation .o f my invention which I iind highly satisfactory. I have not attempted to illus.-

trate or describe other embodments .or adaptatliis .disclosure will enable those ,skilled in the .crt to embody or .adapt my improvements as may be desired.

Hai/ine thus described my invention, what I .claim .as new and vdesire to secure by Letters Patent, is:

1. A piston ring assembly comprising spaced thin .expansible .side members and a `Split expensilgle spacer member intermediatesaid side mem7 bers, said side members being disposed to present their outer edges .to .cylinder wall and disposed to present their `outer side surfaces to the opp-o: site side walls of a piston ring groove. each side member having end portions overlappingapproxi.-V mately 4 one.-hali the .circumference of the side members and haring ,an axially inwardly offset portion disposed .at the attached .end of one end portion and adjacent the free end .of the v.other end portion. .the .odset portion axial .extent bef ine approximately egaal .to the thickness of said adjacent end portion, the offset portion .tins theoutor face .of theslde stantial'ly entirely in. a plane and pennitting said face to engage the side wall of .a ring groove substantially the entire length of the .circumference of .said vside Wall. said o isct portion being .circliraierentially Slightly spaced from said adjacent end .to Permit the side member .to expand and contract in a ring groei/1e, said spacer meinber being vformed of duotile metal folded .upon itself into s plurality .of integrally connected superimposed plies, the bottom wall of the spacer member being upwardly Yloont at spaced intervals to provide alternate spacer and drain reaches, said spacer' member opposite from the split thereof having an axial offset portion to permit the portions on the opposite sides thereof to lie in axially spaced planesl the axially oiset portions of the side members and spacer member be,- ing in substantially axial superimposed relation, the spacer member having a .gap at the split thereof, the inner ends of the side members being integrally connected by an axially extending offset portion disposed in the gap of the spacer member. A

2. A piston ringassembly comprising spaced thin expansi le side members and a split expansible spacer member intermediate said side members.

said side members being disposed to present their outer edges to a cylinder wall and disposed to present their outer side surfaces to the opposite side Walls of apiston ring groove, each side member having end portions overlapping approximately onehalf the circumference of the side members and havingan axially inwardly roffset portion disposed at the attached end of one end portion and ladjacent the free end of the other end portion, the offset portion in axial extent being approximately equal to the thickness of said adjacent endv portion, the oifset portion permitting the outer face of the side member to lie substantially entirely in a plane and permitting said face to engage the side wall of a ringgroove substantially the entire length of the circumference of said side wall, said offset portion being circumferentally slightly spaced from said adjacent end to permit the side member to expand and contract in a ring groove, said spacer member opposite from the split thereof having an axial offset portion to permit the portions on the opposite sides therof to lie in axially spaced planes, the axially offset portions of the side members and spacer member being Yin substantially axial superimposed relation, the spacer member having a gap at the split thereof, the inner ends of the side members being integrally connected by an axiallyextending offset portion disposed in the gap of the spacer member.

3. A piston ring assembly comprising spaced f thin expansible side members and a split expansible spacer member intermediate said side members, said side members being disposed to present their outer edges to a cylinder Wall and disposed to present their outer side surfaces to .1

the opposite side walls of a piston ring groove, each side member having end portions overlapping approximately one-half thevcircumference of the side members and having an axially inwardly offset portion disposed at the attached end of one end portion and adjacent the free end of the other end portion, the offset portion in axial extent being approximately equal to the thickness of said adjacent end portion, the offset portion permitting the outer face of the side member to lie substantially entirely in a plane and permitting said face to engage the side wall of a ring groove substantially the entire length of the circumference of said side Wall, said offset portion being circumferentially slightly spaced from said adjacent end to permit the side member to expand and contract in a ring groove, said spacer member being formed of ductile metal folded upon itself into a plurality of integrally connected superimposed plies, said spacer member opposite from the split thereof having an axial offset portion to permit the portions on the opposite sides thereof to lie in axially spaced planes, the axially offset portions of the side `members and spacer member being in substantially axial superimposed relation, the spacer member having a gap at the split thereof, the inner ends of the side members being integrally connected by an axially extending oifset portion disposed in the gap of the spacer member.

4. A piston ring assembly comprising spaced thin expansible side members and a split expansible spacer member intermediate said side members, each side member having superimposed end portions overlapping each other approximately 180 and each having an axially inwardly offset portion disposed at the attached end of one end portion and adjacent the free end of its other end portion, the axial dimension of the offset portion being substantially equal to the axial thickness ofthe stock ofthe side member, said offset portion being slightly circum-y ferentially spaced from said free end to Vpermit the side member to expand and contract in a ring groove, said spacer member having oil drain passagevvays therethrough and having an axial offset portion to permit the portions of the spacer member on the opposite sides of the said offset portionl to lie in axially spaced planes, the offset portions of the side members and the spacer member being disposed in superimposed relation, the spacerA member having a gap at the split thereof, the inner ends of the side members being integrally connected by an axially extending offset portion disposed in the gap of the spacer member.

5. A piston ring assembly comprising spaced thin expansible side members and a splitl expansible spacer member intermediate said.side members, each side member having superim-Y posed end portions overlapping each other approximately and each having an axially inwardly offset portion disposed at the attached end of one end portion and adjacent the free end of itsk other-end portion, the axial dimension of the offset portion beingrsubstantially equal to the `axial thickness of the Vstock of the side member, said 'offset portionlbeing slightly circumferentially spaced from said free end to permit the side member to vexpand and contract in a ring groove, said spacer member having an axial offset portion to permit the portions .of the spacer member on the opposite sides of the said offset portion to lie in axially spaced planes, the

offset portions ofthe side members and theV spacer member being disposed in superimposed relation, the spacer member having a gap at the split thereof, the inner ends of the side members being integrally connected by an axially extending offset portion disposed in the gap of the spacer member.

6. A piston ring assembly comprising thin expansible spaced upper and lower side members and a split expansible spacer member intermediate said side members, the side members being disposed to present their edge portions to a cylinder wall and their outer surfaces being disposed in planes for engagement with the upper and lower walls of a ring groove throughout substantially the entire circumference of the ring groove, each side member having superimposed end portions overlapping each other for approximately one-half a circumference, the axially inner superimposed end portion of each side member being connected to the body of the ring by a relatively short axial offset portion to permit said end portion to be disposed axially Within the plane of the side member, said spacer member having an axially offset portion opposite the split thereof to permit the sides of the spacer member on the opposite ends of the axially offset portion thereof to be in different planes, the axial offset portions of the side members and spacer member being disposed in substantially parallel superimposed relation, the spacer member having a gap at the split thereof, the inner ends of the side members being integrally connected by an axially extending offset portion disposed in the gap of the spacer member.

'7. In a piston ring assembly, expansible relatively thin side members and a split spacer member disposed intermediate said side members, said side members being disposed to present their edge portions to a cylinder wall, each side member being disposed to lie in a plane to engage a side wall 'of a 'ring groove throughout substantially the entirecircmnference thereof, Aeach side mem.- her having van end portion overlapping its .oppoe site end portion and lying in a plane .axially inwardly offset from said pla-ne of the side inemher, said axially inwardly offset end portion being connected to the side member by an axially orl- Set portion, said spacer member having an axially offset portion to permit the side portions of the spacer member on `the opposite sides of its axially olset portion to lie in axially spaced planes, the portion of the spacer member on one side of said axially offset portion being axially oiset ,throughout substantially its entire length relative the portion of the spacer member on the opposite side of said axially oiset portion, the axiadly olTset portions of the side members and spacer member being in substantially .axial superimposed relation, the overlapping end portions of ,one side. member overlapping one of said axially oiset side portions .of the spacer member and the overlapping end portions of the other side member overlapping the other axially oiTset side portion of thev spacer' member, the spacer member having a gap at the split thereof, the inner ends of the side members being integrally connected by .an axially extending offset portion disposed in the gap ofthe spacer member.

8; In a piston ring assembly, expansible side members and a split expansible spacer member disposed between said side members, said side members having superimposed overlapping end portions, the overlapping end portions of one side member lbeing disposed radially on the opposite side of the ring assembly from that of the over.. l

lapping end portions of Ythe other side member, said spacer member having an axially offset portion substantially spaced from the split thereof to permit the side portions ofthe spacer member on the opposite sides of the axially otlset portion thereof to lie in axially spaced planes, the por tion .of the spacer member .on one 'side of said axially offset portion being axially offset throughout substantially its entire length relative the portion of the spacer member on the opposite 'side of said axially oiset portion, one vof said side por; tions of the spacer member overlappingly engage ing the axially inner end portion of one side member, and the other of said Aside portions of the spacer'member .overlappingly engaging the axially inner end portion of the other side mem.- ber, the spacer member having a gap at the split thereof, the inner ends of the side members being integrally connected by an axially extending olset portion disposed in the gap of the spacer member.

9. In a piston ring assembly, relatively thin expansible axially spaced side members for engaging the opposite side Walls of a piston ring groove, each side member being disposed to present an outer edge portion to a cylinder Wall, each side member being disposed to lie in a plane for approximately 36G and having an axially in- Wardly offset endportion overlapping the oppo site end portion for approximately 180 and lying in a pla-ne parallel to the rst named plane of the side member, said rst named end portion being connected to the side member by an axially ex tending portion slightly circumferentially spaced from the opposite free end of the side member to permit expansion and contraction of the side member in a piston ring groove, the inner ends of spaced side members being integrally con* nected by an axially extending offset portion.

HAROLD P. PHILLIPS.

No references cited; 

